/*
 * Copyright (C) 2012 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect.testing.google;

import static com.google.common.collect.testing.Helpers.assertEqualIgnoringOrder;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEYS;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEY_QUERIES;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUES;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUE_QUERIES;
import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Multimap;
import com.google.common.collect.testing.Helpers;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.MapFeature;

import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;

import org.junit.Ignore;

/**
 * Tests for {@link Multimap#remove(Object, Object)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
public class MultimapRemoveEntryTester<K, V> extends AbstractMultimapTester<K, V, Multimap<K, V>>
{
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testRemoveAbsent()
    {
        assertFalse(multimap().remove(k0(), v1()));
        expectUnchanged();
    }

    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testRemovePresent()
    {
        assertTrue(multimap().remove(k0(), v0()));

        assertFalse(multimap().containsEntry(k0(), v0()));
        expectMissing(e0());
        assertEquals(getNumElements() - 1, multimap().size());
        assertGet(k0(), ImmutableList.<V>of());
    }

    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_KEYS})
    public void testRemoveNullKeyPresent()
    {
        initMultimapWithNullKey();

        assertTrue(multimap().remove(null, getValueForNullKey()));

        expectMissing(Helpers.mapEntry((K) null, getValueForNullKey()));
        assertGet(getKeyForNullValue(), ImmutableList.<V>of());
    }

    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES})
    public void testRemoveNullValuePresent()
    {
        initMultimapWithNullValue();

        assertTrue(multimap().remove(getKeyForNullValue(), null));

        expectMissing(Helpers.mapEntry(getKeyForNullValue(), (V) null));
        assertGet(getKeyForNullValue(), ImmutableList.<V>of());
    }

    @MapFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_KEY_QUERIES})
    public void testRemoveNullKeyAbsent()
    {
        assertFalse(multimap().remove(null, v0()));
        expectUnchanged();
    }

    @MapFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUE_QUERIES})
    public void testRemoveNullValueAbsent()
    {
        assertFalse(multimap().remove(k0(), null));
        expectUnchanged();
    }

    @MapFeature.Require(value = SUPPORTS_REMOVE, absent = ALLOWS_NULL_VALUE_QUERIES)
    public void testRemoveNullValueForbidden()
    {
        try
        {
            multimap().remove(k0(), null);
            fail("Expected NullPointerException");
        }
        catch (NullPointerException expected)
        {
            // success
        }
        expectUnchanged();
    }

    @MapFeature.Require(value = SUPPORTS_REMOVE, absent = ALLOWS_NULL_KEY_QUERIES)
    public void testRemoveNullKeyForbidden()
    {
        try
        {
            multimap().remove(null, v0());
            fail("Expected NullPointerException");
        }
        catch (NullPointerException expected)
        {
            // success
        }
        expectUnchanged();
    }

    @MapFeature.Require(SUPPORTS_REMOVE)
    @CollectionSize.Require(absent = ZERO)
    public void testRemovePropagatesToGet()
    {
        List<Entry<K, V>> entries = Helpers.copyToList(multimap().entries());
        for (Entry<K, V> entry : entries)
        {
            resetContainer();

            K key = entry.getKey();
            V value = entry.getValue();
            Collection<V> collection = multimap().get(key);
            assertNotNull(collection);
            Collection<V> expectedCollection = Helpers.copyToList(collection);

            multimap().remove(key, value);
            expectedCollection.remove(value);

            assertEqualIgnoringOrder(expectedCollection, collection);
            assertEquals(!expectedCollection.isEmpty(), multimap().containsKey(key));
        }
    }

    @MapFeature.Require(SUPPORTS_REMOVE)
    @CollectionSize.Require(absent = ZERO)
    public void testRemovePropagatesToAsMap()
    {
        List<Entry<K, V>> entries = Helpers.copyToList(multimap().entries());
        for (Entry<K, V> entry : entries)
        {
            resetContainer();

            K key = entry.getKey();
            V value = entry.getValue();
            Collection<V> collection = multimap().asMap().get(key);
            assertNotNull(collection);
            Collection<V> expectedCollection = Helpers.copyToList(collection);

            multimap().remove(key, value);
            expectedCollection.remove(value);

            assertEqualIgnoringOrder(expectedCollection, collection);
            assertEquals(!expectedCollection.isEmpty(), multimap().containsKey(key));
        }
    }

    @MapFeature.Require(SUPPORTS_REMOVE)
    @CollectionSize.Require(absent = ZERO)
    public void testRemovePropagatesToAsMapEntrySet()
    {
        List<Entry<K, V>> entries = Helpers.copyToList(multimap().entries());
        for (Entry<K, V> entry : entries)
        {
            resetContainer();

            K key = entry.getKey();
            V value = entry.getValue();

            Iterator<Entry<K, Collection<V>>> asMapItr = multimap().asMap().entrySet().iterator();
            Collection<V> collection = null;
            while (asMapItr.hasNext())
            {
                Entry<K, Collection<V>> asMapEntry = asMapItr.next();
                if (key.equals(asMapEntry.getKey()))
                {
                    collection = asMapEntry.getValue();
                    break;
                }
            }
            assertNotNull(collection);
            Collection<V> expectedCollection = Helpers.copyToList(collection);

            multimap().remove(key, value);
            expectedCollection.remove(value);

            assertEqualIgnoringOrder(expectedCollection, collection);
            assertEquals(!expectedCollection.isEmpty(), multimap().containsKey(key));
        }
    }
}
